20. *Spider-Man's alter ego : PETER PARKER
58. *Striped African equine : PLAINS ZEBRA
11. *Midsize SUV : HONDA PILOT
29. *Hellenic religious symbol : GREEK CROSS
41. Pseudonym ... and what the end of each answer to a starred clue is : PEN NAME
Melissa here. A pseudonym theme after yesterday's NAME CHANGE. Today, each theme answer ends with the brand name of a pen maker. It took all four for the light to come on, as I was expecting to find actual aliases. Northeast was the last to fall, due to an unknown, and a misread clue. Full of Scrabble-y letters, J, K, X - only a Q and V short of a pangram.
Across
1. Blue gem, briefly : LAPIS
6. See : ESPY
10. Units of electrical resistance : OHMS
14. "You __ serious": "I don't believe it" : AREN'T
15. When doubled, toy train sound : CHOO
16. Actress Cusack : JOAN
17. Bungle : MISDO
. If you say so.
18. Don't have : LACK
19. Number after dix : ONZE
. French ten and eleven.
23. DOJ anti-narcotics arm : DEA
. Not ATF.
24. Gen-__: boomers' kids : XERS
25. Lustrous patterned fabric : DAMASK
27. Rim : EDGE
30. SOS responder : USCG
. Coast Guard.
33. Vain dresser : FOP
. Funny word.
34. Protestant minister : PARSON
. Not PASTOR.
36. Leaving out : OMITTING
40. Mined metal : ORE
43. Texter's guffaw : LOL
44. Like shish kebab : SKEWERED
46. A __: based on deduction rather than experience : PRIORI
48. Family reunion attendees : KIN
49. Be an omen of : BODE
51. __ in the back: betray : STAB
52. Prickly plant : CACTUS
55. Burn soother : ALOE
57. "Ben-__" : HUR
64. Superstar : IDOL
66. BMW competitor : AUDI
67. Studio warning sign : ON AIR
68. Sushi bar soup : MISO
69. Corp. VIP : PRES
70. Bump in the night, say : NOISE
71. CancĂșn cash : PESO
72. Place for Girl Scout badges : SASH
73. Furry sci-fi creatures : EWOKS
Down
1. End table accessory : LAMP
2. Soul singer India.__ : ARIE
3. Irksome one : PEST
4. Reference aids in reference books : INDEXES
5. Sock away : STORE
6. Mercedes line of autos : E CLASS
7. __-Pei: wrinkly dog : SHAR
8. Small indentation : POCK
.
9. Hitched together, as oxen : YOKED
10. Spanish eye : OJO
12. Perplexing passages : MAZES
. Not literary passages.
13. Tiptoe, say : SNEAK
21. One shaping a rosebush : PRUNER
22. Roof support : RAFTER
26. Witty remark : MOT
27. Long narrative poem : EPOS
28. Chocolate option : DARK
. Not Milk.
31. Apartment type : CONDO
. Not enough letters for STUDIO.
32. Start-the-day ABC talk show, familiarly : GMA
35. "Let me in!" : OPEN UP
37. Drives forward : IMPELS
38. "You've Got Mail" director Ephron : NORA
. She felt bad about her neck.
39. Smooth-talking : GLIB
42. Platte River st. : NEB
45. Punster : WIT
47. "Finally got it" : I SEE NOW
50. From Copenhagen, e.g. : DANISH
52. Zoo primate : CHIMP
53. WWII hero Murphy : AUDIE
. Also an actor and song-writer.
54. Reactions to fresh comments : SLAPS
56. Depleted atmospheric layer : OZONE
59. Luminous glow : AURA
60. Mid-month date : IDES
61. "Charles in Charge" actor Scott : BAIO
62. Take a chance on : RISK
63. Warring son of Zeus and Hera : ARES
65. Lav, in Leeds : LOO